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Abstract

Although the emotions and learning based on emotional reaction are individual-specific, the main features are consistent among all people. Depending on the emotional states of the persons, various physical and physiological changes can be observed in pulse and breathing, blood flow velocity, hormonal balance, sound properties, face expression and hand movements. The diversity, size and grade of these changes are shaped by different emotional states. Acoustic analysis, which is an objective evaluation method, is used to determine the emotional state of people’s voice characteristics. In this study, the reflection of anxiety disorder in people’s voices was investigated through acoustic parameters. The study is a case-control study in cross-sectional quality. Voice recordings were obtained from healthy people and patients. With acoustic analysis, 122 acoustic parameters were obtained from these voice recordings. The relation of these parameters to anxious state was investigated statistically. According to the results obtained, 42 acoustic parameters are variable in the anxious state. In the anxious state, the subglottic pressure increases and the vocalization of the vowels decreases. The MFCC parameter, which changes in the anxious state, indicates that people can perceive this situation while listening to the speech. It has also been shown that text reading is also effective in triggering the emotions. These findings show that there is a change in the voice in the anxious state and that the acoustic parameters are influenced by the anxious state. For this reason, acoustic analysis can be used as an expert decision support system for the diagnosis of anxiety.

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Authors and Affiliations

Turgut Özseven
Muharrem Düğenci
Ali Doruk
Hilal İ. Kahraman
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Abstract

The role of fungi in the treatment of wastewater has been extensively researched. Many genera of fungi have been employed for the dye decolourization either in living or dead form. In this study, the removal of an acidic dye, Indigo Carmine (IC), from an aqueous solution by biosorption on dead fungus, Pleurotusostreatus, was investigated. The effects of contact time, initial dye concentration, amount of dead biomass, agitation rate and initial pH on dye removal have been determined. Experimental results show that an increase in the amount of dead biomass positively affected the dye removal. The highest removal was obtained at 150-200 rpm. Slightly lower removing activities were found at lower agitation rates. The dye adsorption effi ciency was not affected by pH except minor variation in the pH of 2-8. Color removal was observed to occur rapidly within 60 minutes. The removal of dye by dead biomass of P. ostreatus was clearly dependent on the initial dye concentration of the solution. Dye removal was reduced from 93% to 64% as concentration was increased from 50 to 500 mg/L Indigo Carmine. This study showed that it was possible to remove textile dyes by dead biomass of P. ostreatus.
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Authors and Affiliations

Sibel Kahraman
Filiz Kuru
Demet Dogan
Ozfer Yesilada
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Abstract

Aluminum and its alloys are one of the most favored metal-based materials for engineering applications that require lightweight materials. On the other hand, composites are getting more preferable for different kinds of applications recently. Boron nitride nanotubes (BNNTs) are one of the excellent reinforcement materials for aluminum and its alloys. To enhance mechanical properties of aluminum, BNNTs can be added with different processes. BNNT reinforced aluminum matrix composites also demonstrate extraordinary radiation shielding properties. This study consists of BNNT reinforced aluminum matrix composite production performed by casting method. Since wetting of BNNT in liquid aluminum is an obstacle for casting, various casting techniques were performed to distribute homogeneously in liquid aluminum. Different methods were investigated in an aim to incorporate BNNT into liquid method as reinforcement. It was found that UTS was increased by 20% and elongation at fracture was increased by 170% when BNNT was preheated at 800°C for 30 minutes.
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Authors and Affiliations

B. Nemutlu
1
ORCID: ORCID
O. Kahraman
1
ORCID: ORCID
K. B. Demirel
1
ORCID: ORCID
I. Erkul
1
ORCID: ORCID
M. Cicek
1
ORCID: ORCID
H. Sahin
1
ORCID: ORCID
K.C. Dizdar
1
ORCID: ORCID
D. Dispinar
1
ORCID: ORCID

  1. Istanbul Technical University, Turkey

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